3,511 research outputs found
Microbiological characterization of sourdough and flours for Portuguese traditional maize bread.
El discurs científic i els processos d`institucionalització científica a la sociologia. El cas de la revista Papers (1973-1993)
Els diversos corrents de la sociologia de la ciència sovint han dirigit la seva atenció exclusiva bé a l'estudi dels disscursos científics, bé al de les estructures i interaccions institucionals que els produeixen. Aquest article és un intent de posar en relació aquests dos nivells d'anàlisi i d'aplicar els resultats a l'estudi sociològic de la sociologia. En primer lloc, es formula un sistema conceptual que prova de sintetitzar algunes contribucions d'aquells corrents. En segon lloc, s'aplica aquest sistema a l'anàlisi empírica de la revista Papers, amb la intenció de mostrar que els discursos científics s'han de posar en relació amb les pràctiques socials de les comunitats que els formulen. Els resultats d'aquesta anàlisis palesen l'existència d'efectes perversos al procés d'institucionalització de la sociologia catalana en els últims vint anys; aquests resultats sugereixen la necessitat de revisar els models tradicionals d'institucionalitzacio científica
ORIGIN: metal creation and evolution from the cosmic dawn
Herder, Jan-Willem den et al.ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z = 10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma-Ray Bursts (GRBs) to study their local environments in their host galaxies. This requires the capability to slew the satellite in less than a minute to the GRB location. By studying the chemical composition and properties of clusters of galaxies we can extend the range of exploration to lower redshifts (z-0.2). For this task we need a high-resolution spectral imaging instrument with a large field of view. Using the same instrument, we can also study the so far only partially detected baryons in the Warm-Hot Intergalactic Medium (WHIM). The less dense part of the WHIM will be studied using absorption lines at low redshift in the spectra for GRBs. The ORIGIN mission includes a Transient Event Detector (coded mask with a sensitivity of 0.4 photon/cm2/s in 10 s in the 5–150 keV band) to identify and localize 2000 GRBs over a five year mission, of which -65 GRBs have a redshift > 7. The Cryogenic Imaging Spectrometer, with a spectral resolution of 2.5 eV, a field of view of 30 arcmin and large effective area below 1 keV has the sensitivity to study clusters up to a significant fraction of the virial radius and to map the denser parts of the WHIM (factor 30 higher than achievable with current instruments). The payload is complemented by a Burst InfraRed Telescope to enable onboard red-shift determination of GRBs (hence securing proper follow up of high-z bursts) and also probes the mildly ionized state of the gas. Fast repointing is achieved by a dedicated ControlledMomentum Gyro and a low background is achieved by the selected low Earth orbit.The team likes to express its appreciation for the support of Astrium UK for the present study.Peer Reviewe
El discurs científic i els processos d'institucionalització científica a la sociologia
Els diversos corrents de la sociologia de la ciència sovint han dirigit la seva atenció exclusiva bé a l'estudi dels disscursos científics, bé al de les estructures i interaccions institucionals que els produeixen. Aquest article és un intent de posar en relació aquests dos nivells d'anàlisi i d'aplicar els resultats a l'estudi sociològic de la sociologia. En primer lloc, es formula un sistema conceptual que prova de sintetitzar algunes contribucions d'aquells corrents. En segon lloc, s'aplica aquest sistema a l'anàlisi empírica de la revista Papers, amb la intenció de mostrar que els discursos científics s'han de posar en relació amb les pràctiques socials de les comunitats que els formulen. Els resultats d'aquesta anàlisis palesen l'existència d'efectes perversos al procés d'institucionalització de la sociologia catalana en els últims vint anys; aquests resultats sugereixen la necessitat de revisar els models tradicionals d'institucionalitzacio científica
Bond behaviour of concrete elements strengthened with NSM CFRP laminate strips under wet-dry cycles
In the last years, the near-surface mounted (NSM) technique has been adopted to increase the load carrying capacity of concrete members. Up to now, research was mainly focused on the structural aspects of NSM strengthening of concrete structures. From an extensive bibliographic search performed, no significant information was found concerning to the NSM long-term performance. The present work has the main objective to contribute for the knowledge on durability performance of the NSM technique with CFRP lami-nates submitted to wet-dry cycles by means of direct pullout tests. The influence of the bond length, the groove width and depth, and the number of wet-dry cycles on the bond performance were the main parame-ters analyzed. Thirty five cubic specimens were tested. Digital image correlation method was used, as a com-plementary tool for monitoring the NSM pullout tests. The tests are described, and the obtained results are presented and discussed
Influence of ohmic heating on production of whey protein aggregates
Ohmic Heating (OH) and its associated non-thermal effects due to the presence of an electrical
field and frequency has been triggering the use of this technology for whey protein
functionalization. Whey proteins have increasingly been used as functional ingredients in several
food formulations presenting high nutritional and biological value (i.e., digestibility, amino acid
pattern, and sensory characteristics). The purpose of this study was to characterize early steps of
whey protein isolate denaturation and aggregation kinetics under the influence of OH treatments
by combining different thermal and electrical effects. A multivariate characterization was
performed in order to identify a global pattern in denaturation behaviour of WPI under OH
applied by linking different structural stages, such as protein unfolding, exposure of protein
hydrophobic core, loss of protein solubility and formation of protein aggregates. Results shows
that exposure of reactive free thiol groups involved in molecular unfolding of β-lactoglobulin (β-
lg) can be reduced from 10 to 20 % with OH. The presence of a moderate electric field (up to 12
V/cm) during heating also contributes to a change in the protein aggregation kinetics, as well as
in the shape of the produced whey aggregates. Size growth was significantly reduced from 178
nm to 25 nm (p < 0.05) under influence of OH and transmission electron microscopy (TEM)
discloses the appearance of β-lg small fibrillar aggregates upon the influence of OH. As
conclusion, OH and its capability of fast heating coupled with treatments under relatively low
electrical field strength, contributed to a synergistic effect yielding protein solutions with less
protein aggregates and high amount of soluble proteins during early stages of heating. These
fibril aggregates have a recognized potential to form physical gels, acting as thickeners or gelling
agents in foods, and can be also used for encapsulation of bioactive ingredients. OH provide a
novel method for production of a whey protein matrix with distinctive features and gel-forming
properties
4,9-Diaminoacridines and 4-Aminoacridines as Dual-Stage Antiplasmodial Hits
Multi‐stage drugs have been prioritized in antimalarial drug discovery, as targeting more than one process in the Plasmodium life cycle is likely to increase efficiency, while decreasing the chances of emergence of resistance by the parasite. Herein, we disclose two novel acridine‐based families of compounds that combine the structural features of primaquine and chloroquine. Compounds prepared and studied thus far retained the in vitro activity displayed by the parent drugs against the erythrocytic stages of chloroquine‐sensitive and ‐resistant Plasmodium falciparum strains, and against the hepatic stages of Plasmodium berghei, hence acting as dual‐stage antiplasmodial hits.info:eu-repo/semantics/publishedVersio
Moderate Electric Fields – a processing biotechnological tool
During the latest decade, much research on Ohmic Heating (OH) as electro-heating technology has been addressed, and the effects of its moderate electric fields (MEF) have been addressed aiming at fighting pathogens and improving the nutritional and sensory properties of food. In this piece of research, MEF appeared to be an interesting biotechnological tool for food processing, as well as to be used in bioprocesses at large. Our results show that the presence of MEF during heating contributes to a change in protein aggregation kinetics, as well in the shape of the aggregates obtained, thus highlighting the influence of non-thermal effects. Transmission electron microscopy unveiled that MEF can be used to transform e.g. whey products, containing mainly lactoglobulin in their composition, into in vitro small nano-fibrils which can attract the interest of biomedical sciences. Electro-heating treatment can be designed together with cold gelation for development of entirely biodegradable whey protein-based gels as potential devices for incorporation of nutraceuticals i.e. up to 60% of association efficiency, thus creating novel applications for both food and pharmaceutical industries . Electrical and thermal effects were optimized into a single step treatment to enhance thermal stabilization (i.e. inactivation of microorganisms and enzymes) and extraction of added-value or bioactive compounds (i.e. anthocyanins and phenolic compounds) from plant and fruit tissues. High frequency (25 kHz) and electric field (30 V/cm), combined with high temperatures (up to 90 ºC) were well suited for a significant effect (p < 0.05) upon extraction of phenolic compounds. The electro-heating capacity of applying high heating rates with an accurate temperature control, together with putative electroporation effects on cell tissues (due to presence of alternating electric fields), put forward an interesting solution as processing technology toward biorefinery systems
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